code: def test_pointset(pointset):
      assert pointset.n_points == pointset.points.shape[0]
      assert pointset.n_cells == 0
  
      arr_name = "arr"
      pointset.point_data[arr_name] = np.random.default_rng().random(10)
      assert arr_name in pointset.point_data
  
      # test that points can be modified
      pointset.points[:] = 0
      assert np.allclose(pointset.points, 0)
      pointset.points = np.ones((10, 3))
      assert np.allclose(pointset.points, 1)
  
imports: import numpy
  import pytest
  import vtk
  import pyvista
  from pyvista.core.errors import PointSetCellOperationError, PointSetDimensionReductionError, PointSetNotSupported
label_desc: Use image node_id 4 for calling a global function with example usage: test_pointset(pointset) without return types